The affinity between ARM processors is defined in the MPIDR register.
We can identify which processors are in the same cluster,
and which ones have performance interdependency. We can define the
cpu topology of ARM platform, that is then used by sched_mc and sched_smt.
The default state of sched_mc and sched_smt config is disable.
When enabled, the behavior of the scheduler can be modified with
sched_mc_power_savings and sched_smt_power_savings sysfs interfaces.
Changes since v4 :
* Remove unnecessary parentheses and blank lines
Changes since v3 :
* Update the format of printk message
* Remove blank line
Changes since v2 :
* Update the commit message and some comments
Changes since v1 :
* Update the commit message
* Add read_cpuid_mpidr in arch/arm/include/asm/cputype.h
* Modify header of arch/arm/kernel/topology.c
* Modify tests and manipulation of MPIDR's bitfields
* Modify the place and dependancy of the config
* Modify Noop functions
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Issue manifests as:
In file included from arch/arm/mach-pxa/include/mach/hardware.h:62,
from arch/arm/mach-pxa/include/mach/gpio.h:28,
from /home/jic23/src/kernel/temp-remove/arch/arm/include/asm/gpio.h:5,
from include/linux/gpio.h:7,
from drivers/staging/iio/gyro/adis16080_core.c:8:
/home/jic23/src/kernel/temp-remove/arch/arm/include/asm/cputype.h:57: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'read_cpuid_id'
...
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/return_address.c:37:6: warning: symbol 'return_address' was not declared. Should it be static?
arch/arm/kernel/setup.c:76:14: warning: symbol 'processor_id' was not declared. Should it be static?
arch/arm/kernel/traps.c:259:1: warning: symbol 'die_lock' was not declared. Should it be static?
arch/arm/vfp/vfpmodule.c:156:6: warning: symbol 'vfp_raise_sigfpe' was not declared. Should it be static?
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds the TCM interface to Linux, when active, it will
detect and report TCM memories and sizes early in boot if
present, introduce generic TCM memory handling, provide a
generic TCM memory pool and select TCM memory for the U300
platform.
See the Documentation/arm/tcm.txt for documentation.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
CPU id is changed in Marvell chip. So update the code in cpu_is_xsc3().
Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
ARMv7 SMP hardware can handle the TLB maintenance operations
broadcasting in hardware so that the software can avoid the costly IPIs.
This patch adds the necessary checks (the MMFR3 CPUID register) to avoid
the broadcasting if already supported by the hardware.
(this patch is based on the work done by Tony Thompson @ ARM)
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add asm/cputype.h, moving functions and definitions from asm/system.h
there. Convert all users of 'processor_id' to the more efficient
read_cpuid_id() function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
